where you can compose Western music using a 97 keys simulated midi keyboard.
I study eastern and ancient music and harmony. So I can not use SoundNote for this kind of music (where each note is represented as a fraction. Using middle Do as a base (i.e., base = 260.741 Hz), the next notes are represented by re = 9/8 base, mi = 5/4 base, fa = 4/3 base, sol = 3/2 base, la = 3/2 9/8, si=3/2 5/4)

So my problem is to change the above keyboard so that

the keys have pitches defined using some fractions like the ones mentioned above

The user could simultaneously use his/her computer keyboard with the midi keyboard for music synthesis and polyphony.

For example:

While simultaneously pressing R on computer keyboard and midi button fa on the Mathematica Midi Keyboard the user could hear re + fa continuously (or at least as long as the R key and fa button are pressed.). But when R is released (and midi button fa is still pressed) only fa will be heard.

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